Earth-abundant stable elemental semiconductor red phosphorus-based hybrids for environmental remediation and energy storage applications

The photocatalytic generation of hydrogen and the photodegradation of organic dyes in wastewater using solar light, preferably visible light, have attracted considerable interest because they are clean, low-cost, and environmentally friendly processes. On the other hand, the major drawbacks with traditional photocatalysts are their limited light absorption ability and wide band gap. Therefore, several studies have focused on elemental semiconductor photocatalysts such as red phosphorus (RP) because of its narrow band gap, high absorption ability for the incident solar spectrum, low cost, earth abundance, and easy accessibility, showing great potential for use in numerous industrial applications. The development of RP and its heterojunctions provides promising candidates for utilizing the largest part of the solar energy spectrum. In addition to the photoinduced properties of RP-based nanocomposites, RP-based nanocomposite materials have recently been considered to be good and advanced anodes for lithium-and sodium-ion batteries because of the high theoretical capacity of RP (2596 mA h g(-1)). The present review briefly introduces the recent advances in the development of various strategies for constructing efficient RP-based hybrid structures that are responsive to visible light, followed by a description of the utilization of RP and its composites as electrode materials in lithium-and sodium-ion batteries. Finally, a summary and viewpoint are also presented to highlight future work on the development of high-storage RP-based electrodes and visible-light photocatalystsclos

Hierarchically Grown Urchinlike CdS@ZnO and CdS@Al₂O₃ Heteroarrays for Efficient Visible-Light-Driven Photocatalytic Hydrogen Generation

Nanourchin-shaped narrow-band-gap semiconductor photocatalysts with high surface area combined with good crystallinity result in effective photocatalysis. In this work, the impregnating growth of 1D CdS nanowires onto Al₂O₃ and ZnO templates as cores generates novel urchinlike morphology of CdS@oxide photocatalysts. The CdS@Al₂O₃ and CdS@ZnO nanourchins explicitly show a major role in enhanced hydrogen generation with apparent quantum yields (AQY) of 11% and 15%, respectively. Mechanistically, the template-based CdS can influence the photocatalytic activity in two ways: (i) direct well-dispersed growth of CdS onto the oxide core, leading to a high surface area for enhanced light absorption, and (ii) charge transfer from the conduction band of highly crystalline CdS to that of the oxide, which facilitate efficient charge separation for hydrogen production. Following these two mechanisms, a simple, low-cost, and environmentally friendly hydrothermal strategy is employed to synthesize novel nanourchin-shaped CdS-based heteroarrays. This new morphology stimulates the surface area per unit volume of the photocatalyst and exhibits promising application for photocatalytic water splitting